Scaffolds are thought to be a key element needed for successful cartilage repair treatments,
and this prospective extension study aimed to evaluate long-term structural and clinical
outcomes following osteochondral defect treatment with a cell-free biphasic scaffold.
Structural outcomes were assessed using quantitative 3-D magnetic resonance imaging
(MRI) and morphological segmentation to determine the percentage of defect filling
and repair cartilage T2 relaxation times, and clinical outcomes were determined with
the modified Cincinnati Rating System, and the Knee Injury and Osteoarthritis Outcome
Score (KOOS). Seventeen subjects with osteochondral defects in the knee were treated
with ChondroMimetic scaffolds, from which 15 returned for long-term evaluation at
a mean follow-up of 7.9 +/- 0.3 years. The defects treated were trochlear donor sites
for mosaicplasty in 13 subjects, and medial femoral condyle defects in 2 subjects.
MRI analysis of scaffold-treated defects found a mean total defect filling of 95.2
+/- 3.6%, and a tissue mean T2 relaxation time of 52.5 +/- 4.8 ms, which was identical
to the T2 of ipsilateral control cartilage (52.3 +/- 9.2 ms). The overall modified
Cincinnati Rating System score was statistically significant from baseline (p= 0.0065),
and KOOS subscales were equivalent to other cartilage repair techniques. ChondroMimetic
treatment resulted in a consistently high degree of osteochondral defect filling with
durable, cartilage-like repair tissue at 7.9 years, potentially associated with clinical
improvement.
